Abstract: Taking the tractor headlamp as an example, it first analyzes the design method and process plan of UG injection mold modeling, then establishes the tractor headlamp model, and finally completes the design of the tractor headlamp injection mold. The plastic parts produced by UG simulation of mold opening have no defects such as bubbles, deformation, material shortage and silver lines, and no fusion stripes have been found as a whole, which proves that the injection mold for tractor headlights designed in this paper meets the design requirements.